JP2004095764A - Substrate processor and reflection preventing film forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent uneven coating at the time of coating reflection preventing film material liquid on the surface of a resist film. <P>SOLUTION: Pure water is discharged to a substrate with a resist film, and pure water is supplied to the whole surface of the resist film (a step S2). Then, the substrate is rotated to shake off pure water (a step S3), and then reflection preventing film material liquid is spread over the whole surface of the resist film (steps S4, S5). The surface of the resist film is reformed to be hydrophilic by the pure water supplied. Thus, the reflection preventing film material liquid being solution of water can be uniformly spread without generating uneven coating such as liquid flipping or liquid break. <P>COPYRIGHT: (C)2004,JPO

Description

この結果、純水の供給を行わない場合は基板１０枚中７枚において塗布ムラが発生したが、純水の供給を行った場合は基板１０枚中１枚のみにおいて塗布ムラが発生した。このように、上記塗布手法における十分な塗布ムラの防止効果が確認された。
【００４２】
＜４．他の実施の形態＞
以上、本発明の実施の形態について説明してきたが、この発明は上記実施の形態に限定されるものではなく様々な変形が可能である。
【００４３】
例えば、上記実施の形態では、レジスト膜の表面から純水を振り切った後、反射防止膜材料液を塗布していたが、純水を振り切ることなく反射防止膜材料液を塗布するようにしてもよい。ただしこのような場合は、純水と反射防止膜材料液とが混合して反射防止膜材料液の濃度が変化する可能性があり、また、形成される反射防止膜の膜厚の調整が困難となるため、上記実施の形態のように純水を振り切った後、反射防止膜材料液を塗布することが好ましい。
【００４４】
また、上記実施の形態では、レジスト膜の表面を親水性に改質するための改質媒体として純水を供給するようにしていたが、例えば、アルコールなどの水溶性の液体を改質媒体（液体であれば改質液）として用いてもよい。
【００４５】
また、上記実施の形態の基板処理装置１は、レジスト塗布ユニットなどを備えた装置であったが、反射防止膜を形成する処理のみを行う装置であってもよい。また逆に、露光後の基板上にレジスト膜の現像液を供給することによって現像処理を行う現像処理ユニット等を備えた装置であってもよい。
【００４６】
【発明の効果】
以上、説明したように、請求項１ないし６の発明によれば、フォトレジスト膜の表面が親水性に改質されるため、反射防止膜を形成するための所定の水溶液を塗布する際に生じる液弾きや液割れなどの塗布ムラが防止され、フォトレジスト膜の表面に均一に反射防止膜を形成することができる。
【００４７】
また特に、請求項２および５の発明によれば、フォトレジスト膜の表面の全体に純水を供給することで、該表面を容易に親水性に改質することができる。
【００４８】
また特に、請求項３および６の発明によれば、純水を振り切ることで、形成される反射防止膜の膜厚の調整が容易となる。
【図面の簡単な説明】
【図１】基板処理装置の全体構成の一例を示す図である。
【図２】反射防止膜塗布ユニットの要部概略構成を示す図である。
【図３】反射防止膜塗布ユニットの動作の流れを示す図である。
【符号の説明】
１　　　基板処理装置
１０　　　基板回転機構
２１　　　第１ノズル
３１　　　第２ノズル
４１　　　材料液供給装置
４２　　　純水供給装置
４３，４４　制御弁
ＡＣ　　　反射防止膜塗布ユニット
Ｗ　　　基板[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for forming an anti-reflection film on a surface of a photoresist film formed on a semiconductor substrate, a glass substrate for a liquid crystal display device (hereinafter, referred to as “substrate”).
[0002]
[Prior art]
As is well known, in a substrate product such as a semiconductor or a liquid crystal display, a circuit is formed on the substrate using a photolithography technique. Photolithography is a technique for forming a circuit by processes such as coating, exposing, developing, and etching a photoresist (hereinafter, also simply referred to as “resist”).
[0003]
In circuit formation, with the recent miniaturization of circuits, high precision and high quality of fine processing are required. For this reason, in a recent circuit forming process, an antireflection film is further formed on a resist film formed on a substrate to prevent irregular reflection of light and multiple interference in an exposure process, thereby improving circuit forming accuracy. Like that.
[0004]
The anti-reflection film discharges a predetermined aqueous solution containing an anti-reflection film material (hereinafter, also referred to as “anti-reflection film material solution”) onto the surface of the resist film, and then uses the centrifugal force generated by the rotation of the substrate to reflect light. It is formed by a method of applying the material for the prevention film to the entire substrate. When forming an anti-reflection film, it is important to form the anti-reflection film uniformly on the substrate because it also affects the yield of the substrate product.
[0005]
[Problems to be solved by the invention]
However, while 90% or more of the components of the anti-reflection coating material liquid are water, the surface of the resist film is generally hydrophobic. For this reason, when applying the anti-reflective coating material liquid, application unevenness such as liquid repelling or liquid cracking may occur, and the application unevenness prevents the anti-reflective film from being uniformly formed on the substrate, thereby increasing the yield of the substrate product. The problem that it became worse occurred.
[0006]
The present invention has been made in view of the above problems, and provides a technique capable of preventing application unevenness when applying a predetermined aqueous solution for forming an anti-reflection film on the surface of a photoresist film. The purpose is to:
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1 is a substrate processing apparatus for forming an anti-reflection film by applying a predetermined aqueous solution to the surface of a photoresist film formed on a substrate, wherein Applying a medium to the surface of the photoresist film to modify the surface to be hydrophilic; and applying the predetermined aqueous solution to the surface of the photoresist film that has been modified to be hydrophilic. Means.
[0008]
Further, according to a second aspect of the present invention, in the substrate processing apparatus according to the first aspect, the reforming unit discharges pure water as the reforming medium onto the surface of the photoresist film to thereby improve the surface of the photoresist film. Means for supplying pure water to the whole.
[0009]
According to a third aspect of the present invention, in the substrate processing apparatus according to the second aspect, the modifying means includes means for rotating the substrate so as to shake off pure water supplied to the surface of the photoresist film. It also has more.
[0010]
The invention according to claim 4 is a method for forming an antireflection film by applying a predetermined aqueous solution to a surface of a photoresist film formed on a substrate, wherein a predetermined modifying medium is used for forming the antireflection film. A modification step of applying the predetermined aqueous solution to the surface of the photoresist film that has been modified to be hydrophilic, by applying the predetermined aqueous solution to the surface of the photoresist film that has been modified to be hydrophilic. .
[0011]
According to a fifth aspect of the present invention, in the method for forming an antireflection film according to the fourth aspect, the modifying step discharges pure water as the modified medium onto a surface of the photoresist film. Supplying pure water to the entire surface.
[0012]
According to a sixth aspect of the present invention, in the method of forming an antireflection film according to the fifth aspect, the modifying step includes rotating the substrate so as to shake off pure water supplied to the surface of the photoresist film. , Is further provided.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
<1. Configuration>
FIG. 1 is a diagram illustrating an example of an overall configuration of a substrate processing apparatus 1 according to the present invention. The substrate processing apparatus 1 is an apparatus for performing a process of forming a resist film on a substantially circular substrate and a process of forming an anti-reflection film. The substrate processing apparatus 1 includes three resist coating units SC, an anti-reflection film coating unit AC, A robot TR, an indexer ID, and an interface IF are provided. Above each of the three resist coating units SC and the antireflection film coating units AC, a heat treatment unit (not shown), for example, a hot plate for performing a heating process or a cool plate for performing a cooling process is provided.
[0015]
The indexer ID mounts a carrier (not shown) capable of storing a plurality of substrates and includes a transfer robot, and pays out unprocessed substrates from the carrier to the transport robot TR. Further, the interface IF has a function of receiving a processed substrate from the transport robot TR and passing it to an exposure apparatus (not shown).
[0016]
The transfer robot TR can perform a vertical movement in a vertical direction and a rotational movement about the vertical direction by a drive mechanism (not shown). The transport robot TR transports the substrate among the above-described indexer ID, the three resist coating units SC, the antireflection film coating unit AC, and the interface IF.
[0017]
The resist coating unit SC is a unit that performs resist coating by dropping a resist on the peripheral surface of the substrate while rotating the substrate. The three resist coating units SC have the same function.
[0018]
The anti-reflection film coating unit AC is a unit that forms an anti-reflection film on the substrate by applying a predetermined aqueous solution (anti-reflection film material liquid) containing the anti-reflection film material to the substrate. The substrate targeted by the anti-reflection film coating unit AC is a substrate on which a resist film is formed by applying a resist by the resist coating unit SC and then performing a heat treatment called prebaking by a hot plate. . Therefore, an anti-reflection film (top anti-reflection film / TARC: Top Anti-Reflection Coating) is formed on the surface of the resist film on the substrate.
[0019]
FIG. 2 is a diagram showing a schematic configuration of a main part of the antireflection film coating unit AC. As shown in the figure, the antireflection film coating unit AC mainly includes a substrate rotating mechanism 10 for holding and rotating the substrate W, a first discharge mechanism 20 for discharging the antireflection film material liquid to the substrate W, and a substrate W A second discharge mechanism 30 for discharging pure water, a processing liquid supply unit 40 for supplying an anti-reflection film material liquid, pure water, and the like, and a control unit 50 for controlling each unit of the anti-reflection film coating unit AC. Have.
[0020]
The substrate W is held in a substantially horizontal posture by the spin chuck 11. The spin chuck 11 is a so-called vacuum chuck that holds the substrate W by vacuum-sucking the back surface of the substrate W. Note that a so-called mechanical chuck that mechanically grips the edge of the substrate W may be used as the spin chuck 11.
[0021]
A motor shaft 12 of a spin motor 13 is vertically provided at a central portion on the lower surface side of the spin chuck 11. When the spin motor 13 is driven to rotate the motor shaft 12, the spin chuck 11 and the substrate W held thereon are also rotated in a substantially horizontal plane.
[0022]
Further, the substrate rotating mechanism 10 is provided with a cup 14 for receiving and collecting the processing liquid scattered from the rotating substrate W. The cup 14 is connected to a not-shown cup elevating mechanism, and can be moved up and down relatively to the spin chuck 11. When discharging the antireflection film material liquid or pure water to the substrate W, a cup 14 is arranged around the substrate W held by the spin chuck 11 as shown in FIG. In this state, pure water or the like scattered from the rotating substrate is received by the inner wall surface of the cup 14 and guided to a lower discharge port (not shown). When the transport robot TR carries in / out the substrate W, the cup 14 is arranged so that the spin chuck 11 protrudes from the upper end of the cup 14.
[0023]
The first ejection mechanism 20 mainly includes a first nozzle 21 for ejecting the anti-reflective coating material liquid to the substrate W, an arm 22 holding the first nozzle 21, and a rotation motor 24 for rotating the arm 22. It has.
[0024]
A nozzle 21 is fixed to a distal end portion 22 a of the arm 22, and a rotating shaft 23 is suspended from a base end portion 22 b of the arm 22. Further, a rotating motor 24 is connected to a lower portion of the rotating shaft 23. The arm 22 is disposed above the substrate W so that the longitudinal direction thereof is along the horizontal direction. When the rotation motor 25 is driven, the driving force is transmitted to the arm 22 via the rotation shaft 23, Is rotated in a substantially horizontal plane. The first nozzle 21 can move between the center position of the substrate W and the retracted position retracted from above the substrate W by the pivoting operation of the arm 22.
[0025]
The second ejection mechanism 30 includes a second nozzle 31 for ejecting the substrate W, an arm 32 for holding the second nozzle 31, and a rotation motor 34 for rotating the arm 32. It has substantially the same configuration as the ejection mechanism 20. Therefore, similarly to the first nozzle 21, the second nozzle 31 can be moved between the center position of the substrate W and the retracted position retracted from above the substrate W by the rotation operation of the arm 32.
[0026]
The first nozzle 21 is connected to a material liquid supply device 41 of the processing liquid supply unit 40 via a control valve 43 that is controlled to open and close. On the other hand, the second nozzle 31 is connected to a pure water supply device 42 of the treatment liquid supply unit 40 via a control valve 44 that is controlled to open and close. Thus, the first nozzle 21 is supplied with the anti-reflective coating material liquid from the material liquid supply device 41, and the second nozzle 31 is supplied with pure water from the pure water supply device 42. The amounts of the processing liquid supplied to the first and second nozzles 21 and 31 are adjusted by opening and closing the control valves 43 and 44, respectively.
[0027]
Further, the control unit 50 is configured using a computer having a CPU, a memory, and the like, and is electrically connected to each unit of the antireflection film coating unit AC, and controls the operation of each unit as a whole. The operation control performed by the control unit 50 includes the above-described rotation control of the spin motor 13, the rotation control of the rotation motors 24 and 34, the opening and closing control of the control valves 43 and 44, the elevation control of the cup elevating mechanism, and the like.
[0028]
<2. Operation>
Next, the operation of the antireflection film coating unit AC of the substrate processing apparatus 1 having the above-described configuration will be described. FIG. 3 is a diagram showing a flow of the operation of the antireflection film coating unit AC. Hereinafter, the operation will be described with reference to FIG. 3. Before the start of the operation, both the first and second nozzles 21 and 31 are arranged at the retracted position, the cup 14 is lowered, and the spin chuck 11 is moved. Are protruding from the cup 14.
[0029]
First, the substrate W on which the resist film has been formed by the processing of the resist coating unit SC and the hot plate is transferred from the transport robot TR to the spin chuck 11. When the transferred substrate W is held by the spin chuck 11 in a substantially horizontal posture, the cup 14 is raised to a predetermined position (step S1).
[0030]
Next, the substrate W held thereon is rotated at a predetermined speed together with the spin chuck 11. Subsequently, the arm 32 is rotated to move the second nozzle 31 to the center position of the substrate W, and then a predetermined amount of pure water is discharged from the second nozzle 31. As a result, pure water is supplied to the center position of the substrate W, and the pure water is distributed over the entire substrate W using the centrifugal force due to rotation. That is, by discharging pure water to the surface of the resist film on the substrate W, pure water is supplied to the entire surface of the resist film. By supplying the pure water, the surface of the resist film is modified to be hydrophilic. Therefore, in the present embodiment, pure water is used as a modifying medium for modifying the surface of the resist film to be hydrophilic (step S2).
[0031]
At this time, pure water may be supplied without rotating the substrate W. However, with such rotation, pure water can be supplied to the entire surface of the resist film in a relatively short time.
[0032]
Next, when a predetermined amount of pure water is supplied from the second nozzle 31, the discharge of the pure water is stopped, and the second nozzle 31 is moved to the retreat position. Even after the discharge of the pure water is stopped, the rotation of the substrate W is continued for a predetermined time, and the pure water adhering to the surface of the resist film is shaken off by the centrifugal force of the rotation. When the predetermined time has elapsed, the rotation of the spin chuck 11 and the substrate W held by the spin chuck 11 are stopped (step S3).
[0033]
Due to such rotation of the substrate W, even after pure water is shaken off from the surface of the resist film, a very small amount of pure water that cannot be seen is attached to the surface of the resist film. Sex status is maintained.
[0034]
Next, the first nozzle 21 is moved to the center position of the substrate W by rotating the arm 22. Then, a predetermined amount of the anti-reflection coating material liquid is discharged from the first nozzle 21 to the surface of the resist film on the substrate W whose rotation has been stopped, and the anti-reflection coating material liquid pools at the center position of the substrate W ( Core). Since the surface of the resist film is modified to be hydrophilic by the supply of pure water, the contact angle between the liquid pool and the resist film (the angle formed between the liquid surface and the solid surface) is compared with the case where pure water is not supplied. ) Becomes an acute angle, and the anti-reflective coating material liquid is easily spread on the surface of the resist film (step S4).
[0035]
Next, the substrate W held by the spin chuck 11 is rotated together with the spin chuck 11 at a predetermined speed, and the antireflection film material liquid in the liquid pool is spread over the entire substrate W using the centrifugal force of the rotation (development). Let it do). As a result, the anti-reflective coating material liquid is applied to the entire surface of the resist film, but since the surface of the resist film is modified to be hydrophilic, coating unevenness such as liquid repelling and liquid cracking is prevented. You. Therefore, the anti-reflection coating material liquid is uniformly applied to the entire surface of the resist film (step S5).
[0036]
When the anti-reflection coating material liquid is applied to the entire substrate W, the rotation of the substrate W is stopped, the first nozzle 21 is moved to the retreat position, and the cup 14 is lowered. In this state, the transfer robot TR takes out the substrate W coated with the antireflection film material liquid from the spin chuck 11 and conveys the substrate W, thereby completing a series of operations of the antireflection film coating unit AC (step S6).
[0037]
Thereafter, the substrate W coated with the anti-reflection film material liquid is subjected to a natural drying or a heat treatment using a hot plate, so that a uniform anti-reflection film is formed on the resist film of the substrate W.
[0038]
As described above, in the substrate processing apparatus 1 of the present embodiment, after the surface of the photoresist film is modified to be hydrophilic, the material for the antireflection film is applied to the surface of the photoresist film. Application unevenness such as liquid repelling or liquid cracking that occurs during application is prevented, and an antireflection film can be formed uniformly on the surface of the photoresist film.
[0039]
In addition, since pure water is discharged onto the surface of the photoresist film and pure water is supplied to the entire surface to modify the surface of the photoresist film, the hydrophilicity can be easily modified. it can.
[0040]
<3. Example>
In order to confirm the effect of preventing the coating unevenness in the above coating method, the antireflection coating material liquid was actually applied to the surface of the resist film when pure water was supplied and when it was not supplied. The conditions for implementation are as follows.
[0041]

As a result, when pure water was not supplied, coating unevenness occurred on seven out of ten substrates, but when pure water was supplied, coating unevenness occurred on only one of ten substrates. Thus, a sufficient effect of preventing the application unevenness in the above-described application method was confirmed.
[0042]
<4. Other Embodiments>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications are possible.
[0043]
For example, in the above embodiment, the anti-reflective coating material solution is applied after the pure water is shaken off from the surface of the resist film, but the anti-reflective coating material solution may be applied without shaking the pure water. Good. However, in such a case, there is a possibility that the concentration of the anti-reflection coating material solution changes due to the mixing of the pure water and the anti-reflection coating material solution, and it is difficult to adjust the thickness of the formed anti-reflection coating. Therefore, it is preferable to apply the anti-reflective coating material liquid after shaking off the pure water as in the above embodiment.
[0044]
Further, in the above embodiment, pure water is supplied as a modifying medium for modifying the surface of the resist film to be hydrophilic. For example, a water-soluble liquid such as alcohol may be supplied to the modifying medium ( If it is a liquid, it may be used as a reforming liquid).
[0045]
Further, the substrate processing apparatus 1 of the above-described embodiment is an apparatus including a resist coating unit and the like, but may be an apparatus that performs only a process of forming an antireflection film. Conversely, the apparatus may be provided with a developing unit for performing a developing process by supplying a developing solution for the resist film onto the exposed substrate.
[0046]
【The invention's effect】
As described above, according to the first to sixth aspects of the present invention, since the surface of the photoresist film is modified to be hydrophilic, it occurs when a predetermined aqueous solution for forming an antireflection film is applied. Application unevenness such as liquid repelling and liquid cracking is prevented, and an antireflection film can be uniformly formed on the surface of the photoresist film.
[0047]
In particular, according to the invention of claims 2 and 5, by supplying pure water to the entire surface of the photoresist film, the surface can be easily modified to be hydrophilic.
[0048]
In particular, according to the third and sixth aspects of the present invention, the thickness of the formed antireflection film can be easily adjusted by shaking off the pure water.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of an overall configuration of a substrate processing apparatus.
FIG. 2 is a diagram showing a schematic configuration of a main part of an antireflection film coating unit.
FIG. 3 is a diagram showing a flow of an operation of the antireflection film coating unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 10 Substrate rotation mechanism 21 1st nozzle 31 2nd nozzle 41 Material liquid supply unit 42 Pure water supply units 43 and 44 Control valve AC Antireflection film coating unit W Substrate

Claims (6)

A substrate processing apparatus for forming an antireflection film by applying a predetermined aqueous solution to a surface of a photoresist film formed on a substrate,
Modifying means for modifying the surface to be hydrophilic by applying a predetermined modifying medium to the surface of the photoresist film;
Coating means for applying the predetermined aqueous solution on the surface of the photoresist film modified to hydrophilicity,
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The reforming means,
Means for supplying pure water to the entire surface of the photoresist film by discharging pure water as the modifying medium onto the surface of the photoresist film;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 2,
The reforming means,
Means for rotating the substrate to shake off the pure water supplied to the surface of the photoresist film,
A substrate processing apparatus, further comprising: A method of forming an antireflection film by applying a predetermined aqueous solution on the surface of a photoresist film formed on a substrate,
By applying a predetermined modification medium to the surface of the photoresist film, a modification step of modifying the surface to be hydrophilic,
An application step of applying the predetermined aqueous solution to the surface of the photoresist film that has been modified to be hydrophilic,
A method for forming an antireflection film, comprising: The method for forming an antireflection film according to claim 4,
The reforming step,
Supplying pure water to the entire surface of the photoresist film by discharging pure water as the modifying medium onto the surface of the photoresist film;
A method for forming an antireflection film, comprising: The method for forming an antireflection film according to claim 5,
The reforming step,
Rotating the substrate to shake off the pure water supplied to the surface of the photoresist film,
A method for forming an anti-reflection film, further comprising:

Images